You want to read a large log file line by line and count how many lines contain the word 'error'. Which code snippet correctly does this?

hard🚀 Application Q15 of Q15

Python - File Reading and Writing Strategies

Acount = 0 with open('log.txt') as f: lines = f.readlines() for line in lines: if 'error' in line: count += 1 print(count)

Bcount = 0 with open('log.txt') as f: for line in f: if 'error' in line: count += 1 print(count)

Ccount = 0 f = open('log.txt') lines = f.readlines() for line in lines: if 'error' in line: count += 1 f.close() print(count)

Dcount = 0 with open('log.txt') as f: for line in f: if line == 'error': count += 1 print(count)

Step-by-Step Solution

Solution:

Step 1: Choose efficient line-by-line reading
count = 0 with open('log.txt') as f: for line in f: if 'error' in line: count += 1 print(count) uses 'with open' and iterates file line by line, which is memory efficient for large files.
Step 2: Check condition for counting 'error' in line
count = 0 with open('log.txt') as f: for line in f: if 'error' in line: count += 1 print(count) correctly checks if 'error' is anywhere in the line and increments count.
Final Answer:
count = 0\nwith open('log.txt') as f:\n for line in f:\n if 'error' in line:\n count += 1\nprint(count) -> Option B
Quick Check:
Efficient reading + correct condition = count = 0 with open('log.txt') as f: for line in f: if 'error' in line: count += 1 print(count) [OK]

Quick Trick: Use with open and for line in file for big files [OK]

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